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Troubleshooting
General
If your symptoms are not covered below, check the orientation of all components, connectors and wiring.
Look especially for cold or poor solder joints. Check all DC voltages (see DC voltage chart).
Receiver noise heard when Clock or DSP menus displayed.
This is normal. The main microcontroller in the K2 polls the KDSP2 for information to display about once
per second, waking up all option module processors, which generates noise that is audible at some
frequencies. The K2 does not mute the audio under this circumstance, because you may be listening to a
signal, or wish to synchronize the clock with WWV or some other time standard broadcast. If you wish to
leave the clock display on for long periods of time, simply turn down the receiver’s AF GAIN control or
use the squelch menu entry (
SLCH
in the K2 secondary menu).
Error messages.
If you see
not inst
in the K2 display when you press
AFIL
or tap
DISPLAY
, the KDSP2’s
microcontroller (U1) may not be functioning. Make sure it isn’t installed backwards. Also check for bent
pins, check voltages on all pins, etc. Remove and re-install U3 in case dirt, dust or other problems are
interfering with good electrical contact between the IC and the socket. Try turning power off and back on.
AFIL
works but I can’t access DSP or clock menus when I press
DISPLAY .
The auxbus has lost synchronization. Turn the K2 off and then on again and it should clear. Please let us
know if this happens frequently in your radio.
Loud audio POP when K2 turned on.
If this is much louder than the normal turn-on transient when powering up the K2, set the AF GAIN control
to minimum and cycle power again. If the POP is only present when the AF GAIN control is advanced, it
may indicate the muting circuitry is not working properly on the KDSP2. Check R14, R19, Q5, Q6, Q7
and C8. Also check that U1 pin 14 is not bent or folded under the chip.
Weak or no audio at some filter settings.
If the KDSP2 filter is set to a frequency outside the XFIL range of the K2, it is normal for little or no audio
to be heard. Be sure your XFIL setting and BFO frequency are such that audio will be present in the
selected KDSP2 filter setting.
Filters don’t seem to be at the right frequency or pitch.
If the KDSP2 seems to work OK but some filters don’t seem to be at the correct pitch, try this test. Set the
K2 to its widest filter setting in CW mode. Connect an antenna and find a noisy band or use a noise
